On Tue, Mar 6, 2018 at 10:22 AM, Sowmini Varadhan
<sowmini.varad...@oracle.com> wrote:
> Commit 401910db4cd4 ("rds: deliver zerocopy completion notification
> with data") removes support fo r zerocopy completion notification
> on the sk_error_queue, thus we no longer need to track the cookie
> information in sk_buff structures.
>
> This commit removes the struct sk_buff_head rs_zcookie_queue by
> a simpler list that results in a smaller memory footprint as well
> as more efficient memory_allocation time.
>
> Signed-off-by: Sowmini Varadhan <sowmini.varad...@oracle.com>
Acked-by: Willem de Bruijn <will...@google.com>
> static void rds_rm_zerocopy_callback(struct rds_sock *rs,
> struct rds_znotifier *znotif)
> {
> - struct sk_buff *skb, *tail;
> - unsigned long flags;
> - struct sk_buff_head *q;
> + struct rds_msg_zcopy_info *info;
> + struct rds_msg_zcopy_queue *q;
> u32 cookie = znotif->z_cookie;
> struct rds_zcopy_cookies *ck;
> + struct list_head *head;
> + unsigned long flags;
>
> + mm_unaccount_pinned_pages(&znotif->z_mmp);
> q = &rs->rs_zcookie_queue;
> spin_lock_irqsave(&q->lock, flags);
> - tail = skb_peek_tail(q);
> -
> - if (tail && skb_zcookie_add(tail, cookie)) {
> - spin_unlock_irqrestore(&q->lock, flags);
> - mm_unaccount_pinned_pages(&znotif->z_mmp);
> - consume_skb(rds_skb_from_znotifier(znotif));
> - /* caller invokes rds_wake_sk_sleep() */
> - return;
> + head = &q->zcookie_head;
> + if (!list_empty(head)) {
> + info = list_entry(head, struct rds_msg_zcopy_info,
> + rs_zcookie_next);
> + if (info && rds_zcookie_add(info, cookie)) {
small nit: the test for info will always succeed.
